User Manual

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Place the 2 units in physically separate locations and apply power to them.
The statistics will clear when power is cycled, but they will need to be cleared
manually after each test if power is not cycled.
Connect each individual PC serial port to each of the units and verify the
correct destination address is typed in the address field on the top of the test
tool. Type a short message into the “RF Data” window of the initiating
device. The message can be any text or numbers. If no message is entered
it will not be possible to transmit.
Set the “Repeat Delay” to 100 msec if it isn’t already set. Click the “Send
Single Repeated Msg” button to start transmission. The radio will send
messages repeatedly with 100mSec in between messages until the “Stop
Repeat” button is clicked.
Allow the test to run for some convenient amount of time and then stop
transmission. Go to the “Statistics” screen of the initiating device and select
the “Query Statistics” command button and record the packets sent in the
Transceiver section of the test tool. Next select “Query Statistics” on the
receive device and record packets received in the Transceiver section of the
Statistics page. Link success is simply the ratio of the “Packets Received” to
the “Packets Sent”.
This test will give the raw performance of the link in one direction without
retries. It is a good indicator of the RF environment in which the radios are
being used. High levels of noise or other products operating in the 2.4 GHz
band can cause lower packet success rates.
4.3.2 Round Trip Test
To test the ability of the system to retry messages in a noisy environment, it
is necessary to use a round trip test where the remote end can acknowledge
receipt of packets. Use the setup screen as shown in Figure 4-7 thru 4-9 for
each respective device, but enable acknowledgements on both devices
(Refer to RF Settings Page).
Perform the test in the same manner as the single ended test. Run enough
transmissions to get a statistically valid sampling of the radio environment
over a reasonable period of time.
Look at the “Statistics” screen on the initiating radio to find the total number
of packets sent. Link quality is displayed in the Pkt Success Rate w/Acks
text box. Total link success is the ratio of “Acks Received” to “Packets
Sent”.